Base, sub-base and subgrade aggregate used in road construction projects is often not available in a gradation or quality which meets specifications or which has the desired physical characteristics. Also, some soils or aggregates which meet specification may require beneficiation to provide additional strength. The improvement of strength and other physical characteristics of construction soils or aggregates may be achieved by stabilizing the material.
Examples of known soil or aggregate stabilizing agents include lime and fly-ash mixtures, portland cement, asphalt, asphaltic emulsion, and lignosulfonates. However, although there are applications where satisfactory results may be achieved with the use of such agents, their use may be expensive and may be limited depending upon aggregate characteristics. For example, while asphaltic emulsion is a desirable flexible waterproofing agent, is can be difficult to mix into high fines aggregate. Similarly, while lignosulfonate such as calcium lignosulfonate is relatively inexpensive and has dispersive properties, it is brittle and water soluble upon solidification.
Ideally, a soil or aggregate stabilizing agent should not only provide cementatious properties to the soil or aggregate/stabilizer mixture, but should also impart some waterproofing or hydrophobic characteristics to the treated soil or aggregate. In addition, the agent should be inexpensive and easy to apply.
Accordingly, it is an object of the present invention to provide a new and improved agent for stabilizing soils or aggregates, including soils or aggregates such as those used in road or similar construction.
A further object of the present invention is to provide a stabilizing agent that retains the desirable properties, while avoiding or minimizing the undesirable properties, of know stabilizing agents such as those identified above.
A still further object of the present invention is to provide a stabilizing agent that may be easily prepared and applied in the construction of roads.